Quantitative analysis of vitamin A degradation by Raman spectroscopy.

Vitamin A is known to support cell growth promotion, maintenance, and differentiation of epithelial tissues. Retinol is currently used in cosmetic formulations and products to deliver these and other benefits to the skin. However, retinol is known to be unstable and, therefore, remains of great concern to the cosmetic industry. The decomposition pathways of the retinoids in general have been previously postulated and investigated mostly by high-performance liquid chromatography (HPLC) with UV/Vis spectroscopy. In our studies, we examined specific conditions at which retinol degrades and subsequently identified and quantified the products of retinol decomposition by Raman spectroscopy. We reveal which experimental settings and computational tools allow monitoring of in situ evolution of an all-trans retinol solution when submitted to UV light in the presence of oxygen.